Visual Balloon-Guided Point-By-Point Ablation: Reliable, Reproducible, and Persistent Pulmonary Vein Isolation
Background—While conceptually straightforward, placing point-to-point contiguous radiofrequency lesions to achieve pulmonary vein isolation (PVI) is technically challenging in patients with paroxysmal atrial fibrillation (PAF). Furthermore, chronic efficacy is limited by late PV reconnections. A novel compliant balloon ablation catheter (BAC) able to deliver visually-guided short arcs/spots of laser energy was tested in initial pre-clinical and clinical cases to determine if visual guidance could predict reliable and persistent PVI.
Methods and Results—This study consisted of i) an experimental porcine phase with both acute (n=15 pigs) and 4-week chronic (n=10) data, and ii) a single-center clinical feasibility phase (n=27 PAF patients), again with acute and 3-month chronic data. Under endoscopic guidance, point-by-point peri-venous ablation was performed in a contiguous and overlapping manner. Each porcine PV was longitudinally sectioned for detailed histological analysis. At 3-months post-ablation, patients underwent a pre-specified remapping procedure regardless of symptomotology. In the acute and chronic animals, 29/30 (97%) PVs were electrically isolated after placing the initial circumferential lesion set. For the 4-week chronic animals, 80% of PVs remained isolated; lesions were histologically circumferential in 120/120 (100%) PV sections, and transmural in 116/120 (96.7%) PV sections (average transmurality = 99.0±5.5%). In patients, 100% of the PVs were isolated after 1.3 attempts/PV - 84% of them (85/101) isolated after the initial visually-guided lesion set. At 3 months, 61/68 (90%) PVs continued to be electrically isolated.
Conclusions—Using a visually-guided, compliant balloon ablation catheter with point-by-point ablative capability, PV isolation can be achieved in a reliable, reproducible, and persistent manner.
- Received December 22, 2009.
- Accepted April 2, 2010.
- Copyright © 2010, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited